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  <div class="section" id="numpy-lib-stride-tricks-as-strided">
<h1>numpy.lib.stride_tricks.as_strided<a class="headerlink" href="#numpy-lib-stride-tricks-as-strided" title="Permalink to this headline">¶</a></h1>
<dl class="function">
<dt id="numpy.lib.stride_tricks.as_strided">
<code class="sig-prename descclassname">numpy.lib.stride_tricks.</code><code class="sig-name descname">as_strided</code><span class="sig-paren">(</span><em class="sig-param">x</em>, <em class="sig-param">shape=None</em>, <em class="sig-param">strides=None</em>, <em class="sig-param">subok=False</em>, <em class="sig-param">writeable=True</em><span class="sig-paren">)</span><a class="reference external" href="https://github.com/numpy/numpy/blob/v1.18.1/numpy/lib/stride_tricks.py#L39-L113"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#numpy.lib.stride_tricks.as_strided" title="Permalink to this definition">¶</a></dt>
<dd><p>Create a view into the array with the given shape and strides.</p>
<div class="admonition warning">
<p class="admonition-title">Warning</p>
<p>This function has to be used with extreme care, see notes.</p>
</div>
<dl class="field-list">
<dt class="field-odd">Parameters</dt>
<dd class="field-odd"><dl>
<dt><strong>x</strong><span class="classifier">ndarray</span></dt><dd><p>Array to create a new.</p>
</dd>
<dt><strong>shape</strong><span class="classifier">sequence of int, optional</span></dt><dd><p>The shape of the new array. Defaults to <code class="docutils literal notranslate"><span class="pre">x.shape</span></code>.</p>
</dd>
<dt><strong>strides</strong><span class="classifier">sequence of int, optional</span></dt><dd><p>The strides of the new array. Defaults to <code class="docutils literal notranslate"><span class="pre">x.strides</span></code>.</p>
</dd>
<dt><strong>subok</strong><span class="classifier">bool, optional</span></dt><dd><div class="versionadded">
<p><span class="versionmodified added">New in version 1.10.</span></p>
</div>
<p>If True, subclasses are preserved.</p>
</dd>
<dt><strong>writeable</strong><span class="classifier">bool, optional</span></dt><dd><div class="versionadded">
<p><span class="versionmodified added">New in version 1.12.</span></p>
</div>
<p>If set to False, the returned array will always be readonly.
Otherwise it will be writable if the original array was. It
is advisable to set this to False if possible (see Notes).</p>
</dd>
</dl>
</dd>
<dt class="field-even">Returns</dt>
<dd class="field-even"><dl class="simple">
<dt><strong>view</strong><span class="classifier">ndarray</span></dt><dd></dd>
</dl>
</dd>
</dl>
<div class="admonition seealso">
<p class="admonition-title">See also</p>
<dl class="simple">
<dt><code class="xref py py-obj docutils literal notranslate"><span class="pre">broadcast_to</span></code></dt><dd><p>broadcast an array to a given shape.</p>
</dd>
<dt><code class="xref py py-obj docutils literal notranslate"><span class="pre">reshape</span></code></dt><dd><p>reshape an array.</p>
</dd>
</dl>
</div>
<p class="rubric">Notes</p>
<p><code class="docutils literal notranslate"><span class="pre">as_strided</span></code> creates a view into the array given the exact strides
and shape. This means it manipulates the internal data structure of
ndarray and, if done incorrectly, the array elements can point to
invalid memory and can corrupt results or crash your program.
It is advisable to always use the original <code class="docutils literal notranslate"><span class="pre">x.strides</span></code> when
calculating new strides to avoid reliance on a contiguous memory
layout.</p>
<p>Furthermore, arrays created with this function often contain self
overlapping memory, so that two elements are identical.
Vectorized write operations on such arrays will typically be
unpredictable. They may even give different results for small, large,
or transposed arrays.
Since writing to these arrays has to be tested and done with great
care, you may want to use <code class="docutils literal notranslate"><span class="pre">writeable=False</span></code> to avoid accidental write
operations.</p>
<p>For these reasons it is advisable to avoid <code class="docutils literal notranslate"><span class="pre">as_strided</span></code> when
possible.</p>
</dd></dl>

</div>


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